Dough extrusion device



June 13, 1950 F v R, scHMlTT V 2,511,826

. DOUGH EXTRUSION DEVICE Filed March 19. 1946 3 Sheets-Sheet l FRANK R.5CH/w77 .lune 13, 1950 y F. R. scHMl'rT 2,511,826

DOUGH EXTRUSION DEVICE Filed March 19, 1946 s sheets-sheet 2 A T TUR/VEX June' 13, 1950 F. R. scHMrrT DOUGH EXTRUSION DEVICE 3 Sheets-Sheet 5Filed March 19, 1946 trusion devices of the die expressing type.

positive in operation.

Patented June 13, 1950 UNITED STATES PATENT-FF1CE l DOUGH EXTRUsIoNnevica Frank R. Schmitt, Queens Village, N. Y., assigner.

to Charles A. Morton, Baldwin, N. Y.

Application March 19, 1946, Serial No."f;6\5 `5,410

sclaims. (crier-14)...

'iinished product.

Another object is the substantial elimination of'wastage of the plasticmaterial.

Another object is an extrusion device `Which 'can'4 be reloaded whilethe machine is in operajtion thus eiecting continuous lfeeding thereofwhile in use.

f Another 'object is a simple compact extrusion device which can bequickly dis-assembled, readilyv cleaned and rapidly re-assembled forfurther USE.

Another object is an extrusion device which is Another object is anextrusion device which can be quickly and effectivelyregulated at will,for positively instantaneously and accurately varyfing the size of theextrusions. n Another object is an extrusion device of ruggedconstruction with butfew and simple parts.

Another object is an extrusion device which utilizes standard`I partsordinarily procurable upon the open market, thereby reducing the needfor special parts.

' Another object is an extrusion device which is pneumatically actuatedthereby eliminating 'the need for drive shafts, gearing, and the likefor inter-connecting said device with some ex'- ternal source ofmechanical energy.

Other o jects will appear fromthe detailed Adescription which follows:

In accordance with' this invention the plastic material is deposited inan open continuous feed hopper of the gravity type, said hopperincluding 4,vacuum and compressed air chambers forming an integral partof the hopper casting, and vis then Vprogressed in measured units bymeans of4 a valve controlled mechanism of which said vacuum andcompressed air chambers form a part towards a valved extrusion outletwhich includes the conventional forming and cutting die for forming,anclfsevering annular (or other)` formations of the extruded plastic,characterizedy in this, that rthe-valve""mechanisms are actuated byelectro'- the drawings.

magnetically controlled but pneumatically driven servo-motors whosecycle of operations is positively -initiated and directed over suitableelectricalcircuits which are opened and closed in properly timedsequence.

- Inl the drawings comprising three sheets :of

'four figures numbered Figs. y1 to 4 inclusive:

vFighl is a'vertical cross sectional View of the extrusion vdeviceshowingv certain of the parts partially broken away;

Fig. 2 is afschematic wiring diagram ofthe electrical control circuits;y

Fign'S isan end viewiofA one pair of solenoids, and certainassociatedparts; and 1 Fig. 4 isa side elevation of the extrusion device.

Like reference characters designate kcorresponding parts throughout theseveral figures of The hopper casting l0 preferably includesa. hollowpedestalY base 60, a common vacuum chamber I5, a common compressed airchamber 24, and one or more cylinders 20, all cast in one unit. Thecommon hopper 'IU lwhich is of the gravity feed AtypeL/ispro'vided withdownwardly inclined 'tapering' side walls terminating in one or moredeliverythroats each delivery throat forming `a valve seat'29. Thecommonchambers l5 and 24 yconnect with each of the Acylinders 20. Eachcylinder 2U has a piston valve2l reciprocably mounted therein.'The'coinmon chambers l5 vand 24 are prieurnatically connected to` anyVsuitable exterior source oivacuum and compressed air supply (notshown)L [such-as a pneumatic pump system or a vacuum-pressure pump, insuch a manner that 'the `p'lressureinfthe chamber I5 may be reducedbelovv atmospheric pressure-over the vacuum supply pipe |00,V while thepressure in the chamber 24 is maintained substantially above atmosphericpressure'iover lthe compressed air supply pipe vIt): so thatvthechamber'24 constitutes a4 compressed air chamber, and the chamber l5may constitute a vacuum chamber.

' The chamber I5 is providedwith an air port 25 extending through theWall of the cylinder Y'2li and adapted to-register with a control Aport26"extending through the wall of piston valve 2l;` Similarly air chamber24 is provided with 1 a conrlpressedv air port 22 adapted to registerwith a control port y23in the wall of the piston valve 2l. vTo insure aproper seal between the wall of the pistonfvalve 2| and the wall of thecylin- `der 20, the grooves formedin the head of piston valvev'l-v `mayeither' be -lled withl yan edible grease, or' "may" containv a series ofpiston rings,

The lower end of each piston valve 2| is reduced to form an annularshoulder and seat 2l for its associated sleeve valve 28 which abuts theshoulder and is secured upon the seat 21 in any preferred manner, as bya pressed fit. Each sleeve valve 28 intermittently engages the valveseat formed by the bore of its delivery throat 29 to interrupt thedownward displacement of the plastic materialjS `from the hopper l intothe inner sleeve 36 of -its 'associated forming and cutting die. In theposition shown in Fig. 1 of the drawings a piston valve 2| has reachedthe lower limit of its downward movementand the sleeve valve 28 isseated against the"valve seat formed by the bore of the delivery throat29,.thus momentarily sealing off all communicationbetween the hopper llland inner `sleeve 36. As the operating cycle continues "piston -valve 2|moves upwards in its cylinder thus` .lifting sleeve valve 28 out of itsseat in the bore of the ydelivery throat v29* to re-establishcommunication between hopper I0 and inner sleeve 36.

Each piston valve 2| is slidably-actuatedin its associated cylinder 2 0in any suitable manner as by means of a removablelink `Il which may beattached to piston valve 2| by a wrist pin I9 and to thepiston'oscill'atingv lever VI6 by apin I8. T-he piston oscillating leverI6 isrockably sup- ,vported by thehcommonrocking shaft -|2, which isjournalled in the bracketbearing A sleeve bushing I3 may be inserted inthe hub of the lever arm |6. The leverarm |6 is rockably operated by thepiston rod 86 of aservo-motor 6l in a manner hereinafter-morefullydescribed..A

Each forming and cutting die mechanism .(Figs l and 4) includes an innersleeve 36 which is detachably attached to y an exterior flangelsurrounding its associated delivery throat-29 in any rj oreferr-edmanner, as by means vo'f a collar 3| drilled to receive Asuitablemachine screws 30-30 which are threadably anchored in the hopper ange.An outer sleeve `or sleeve cutter is lmounted for telescopic movementrelativeto each `inner sleeve 36. Ihe upper end of each .sleeve cutter35'terminatesin a collar- 32having 'an vannular groove V'formed thereinfor receiving the Erllers V3'4-34 which are rotatably mounted upon thepins 33-13-3 of aforked rocker ar1n`41. The rocker arms A[4l arefkeye'd`toacommon rocking shaft 48, which is journalled in a'bearing '46 of thebracket which forms an integr-al part of the hopper casting l0. Therocking motion .of the rocker arms 4l ,imparts axial sliding movement totheir associated sleeve cutters 35. Each forming die 39 may be ofanypreferredshape .dependent upon the. desired contour of the plasticformation 4| to be extruded through Athe exl.trusion outlet between theforming die and the cutting die 36.l

As illustrated the machine is designedto exltrude annular formations ofplastic material such -as raw doughnuts made 'frombatten hence theforming die 39 as shown isa kdisc having-,reJ bevyelled cutting edge.Each forming die 39 may be .detachably mounted in spaced` relation ytothe die stem'42 is detachably supported in aspi`der 44 which may bedetachablysecured to the wall of its associated inner sleeve36inanysuitable manner as by means of the grub screws 43-43.

A.The-lower edgeof each inner sleeve'3`6 andiof each ,sleeve cutter 35areYreverselybevelledand the same y general manner.

bevelled at 38 and 3l respectively, each bevel 31 providing a sharpcutting edge for severing each formation of plastic material 4I. Eachsleeve cutter 35 operates telescopically to intermittently close andre-open the extrusion outlet between the bevelled edge 38 of itsassociated sleeve 36 and the periphery of its associated forming die 33.At the lower limit of the teles'copic 'action of each sleeve cutter 35,itsfbevelled cutting edge 31 projects beyond the periphery of itsforming die 39, so that each forming die 39 enters within the opening ofits sleeve cutter 35 Withsuicient clearance to lubricate theirinterengaging surfaces and prevent any binding actontherebetween.

The'rocking motion of rocker arm 41 is effected by the piston rod 8| ofthe pneumatically driven piston'63 of servo-motor 64, the reciprocating:motion of the piston rod 8| being translated into a rocking motion by.means of the block Silslidably nesting in theforked extremity .of thelever arm 9| which .is keyed to the common shaft 48 to which Athe rockerarms 4l are also keyed. Piston rod 8| is ,slidably journalled Theservo-motor 64 which controls theoperation of the sleevecutters 35, andthe servomotor 61 which .controlsthe operation` of the rpiston valves 2|are constructed and function Yin .'lhe servo-motor. includes thesolenoid windings ,19 .and B9 .and their associated solenoid plungersA48 and 49a .which are mounted .for axial sliding,Y movement in the eldsof their .respective solenoid windings, the direction ofmovement beingdependentupon which solenoid winding 'i9 or, is electro-magneticallyenergized. .The cores 49and yMlwfand the piston rod 53 are providedwith..trunnions A52-52 nestingin the forked endsof `thelever armsEll-.58. Theleverarms .5G-Mare keyed .to

acommon shaft 5I, so that whenever either sole- 53 and its piston valve5l. vPiston valve51 reciprocates initspneumatic cylinder .6| under`control ofthe solenoids 1:9 .andfin such a manner :that when solenoid 19is energized the piston valve 5l is idriveninto the cylinder..6| .(Fig..1) .until .the-.port 59lin .piston .valve A5l. registers rwith.connecting port .62 :to supply.comrnessed air from .air pipe 56..to thehead of .thepneumatic-plunger 63 while at the same time ventingthecylinder ,compartment behind thepneumatio plunger63 to :atmosphere by.way of connecting.port.55. and. ex-

haust port 54. .Thecompressed air. drivesApneumaticplunger 63 .to the'opposite end of the cylinder 65, thus reciprocating.-pistonrodl carryingysliding block '.90 to actuate the forked extremity of the'lever arm"9|whichrockstheshaft 48and .the rocker arms llwhich4 in turnmove thesleeve :cutters 35` under. the controlof the rcllers-.34-34,

toa-position substantially as shown in .dotted outlinein Fig. 1 Yof thedrawings. .In this v.position .the bevelled cutting edges .-31 ofsleevecutters ,35

moveoverand .beyondthebevelled edges ofthe .forming dies-.39 toseverand.release the ,plastic formations 4| extruded from the inner .sleeves 36oversaid forming dies. Whenthgsolenoid .is energized, the l.pistonvalve-'51 is.,drawn tothe .oppositeend of its cylinderl ,by Ytherockingmovementof common shaftf5| andthe front .end

of the pneumatic i chamber '.565 uis vented -toatmosphere by Kway of'connecting-portie! andex- 'haust port 58. v.Port 59 of=pistonvalve51 nowregisters with connecting port ..555 tosupply compressed air from pipe56 `behind-"thepneumatic plunger'63 thus driving the `pneumatic plungerinto the cylinder 65 to a positionvsubstantially as shown in Fig. 1` ofthe drawings. 'i Piston rod 8| now moves the lever arm 9| 4androckingshaft 48 to rock the rocker arms 41 inthe oppcsitedirection thusreturning each sleeve cutter 35 to the position substantially as shownin solid lines in Fig. `1 of the drawings. As thewinding of each of thesolenoids 19 and 86 are electro-magnetically energized'and de-energizedin succession, ythe piston valve 51 reciprocates back and forth f-undercontrol of its forked lever 5l) and the common rocking shaft 5| drivenby the lsolenoid plungers 49 or 49a, thus alternately subjecting theopposite sides of the pneumatic plunger 63 to corresponding changes inpneumatic pressure to reciprocate the pneumatic plunger 63 and pistonrod 8| back and forth, thus rocking rocker arms '41 to move the sleevecutters 35 up and down in the manner previously described.

- In like manner the piston valves 2| reciprocatein their respectivecylinders under control of the piston oscillating lever |16 driven bythe pneumatic piston 13 of servo-motor 61 which is identical inconstruction and mode of operation to servo-motor 64 previouslydescribed. The solenoid plungers 14 'fand 14a of the solenoids 84 and 85oscillate back and forth v'in' tandem to rock, and `rocked by, theircommon rockingshaft 15 and the forked lever arms 98.-98. This movespiston or slide valve 69 to'one end or the other of its cylinder 68, toconnect compressedk :air pipe 66 with one of the connecting ports 1|) or1| dependent upon the position of slide valve 69, thus supplyingcompressed air to one side or the other of the pneumatic piston 13 toreciprocate piston rod 88 and rock piston oscillating lever arm I6 upand down to raise and lower eachpistonvalve 2 I, thus intermittentlyinterconnecting the hopper 0 Iwith each delivery throat 29, to controlthe downward displacement of the plastic material from thehopper I8 intoeachinner sleeve 36 in the man-- ner previously described'. 4

The herein described extrusion machine is designed for use inlconjunction with anapparatus of the conveyor type such as a doughnut`frying machine for cooking doughnuts maderfrom dough. or batter.Doughnut fryingmachi'nesof the con-v veyor type are well known. In suchmachines, the conveyor is quite generally drivenrby an electric: motoror other prime-mover mechanically coupled vto a conveyor shaft suchas-,the conveyor shaft 93 (Fig. 2), which in thiscaseis modiiied by theaddition of one or more cams to form a timingshaft 93 which controlsthe-movement [ofl the contact switches 16, 11 and -18'Which are' mountedupon' the timingshaft 93 in such a manner that the cam(s) closes vthenormally open. contact switches 16, 11 and 18,` inpredetermined cyclicorder. u j A j The piston rod 8l of servo-motor 64 is furnished with acam l82 for closing'the contact switch '831 after the piston rod 8|moves off-normal. Similarly piston rod 86 of servo-motor 6'1 is providedwith a control cam 81 for closing contact switch 88 after the piston rod86moves off-normal. All of the control circuits however, areineffective: until the 'manually operated mainswitch 89 is: closed.V f

v While for purposes `of illustration, onlyone valve piston- 2|-, sleevevalVe28, and forming and cutting die 39-35, has been shown in sectionalde tail, it should be understood that the hopper casting is usuallyprovided, with two or more individual piston cylinders 29, piston valves2|, and sleeves 28, having access by means of additional vacuum, air,and control, ports, to the common vacuum chamber, and the commoncompressed air chamber, respectively, and with two or more extrusionoutlets, each equipped with forming die 39 and a cutting die 35, asshown generally in Fig. 4 of the drawings. The servomotor 61 kand shaft|2 form a common control and drive mechanism for all of the valvepistons 2|, and the servo-motor 64 and shaft 48 a com- .mon control anddrive mechanism for all of the types of control device are known tothose skilled in the art but the Mercoid automatic control devicemanufactured by the Mercoid Corporation of Chicago, Ill. may be usedwith satisfactory results.

By regulating the degree of pressure 0f the compressed air in compressedair chamber 24, and the throw of the pneumatic piston 63 controlled byset screw 91 the weight of the plastic formation 4| may be accuratelyregulated. When the plastic formation 4| is a raw doughnut it isaccordingly possible to regulate the weight of the ultimate product toproduce any selected size vof conventional doughnut.

The compressed air which escapes from the various exhaust ports, such asthe exhaust ports 54 and 58, impinges against the wall of the hopper |0and expands, thus absorbing heat from the wall of the hopper and fromthe air in the region of the hopper. This tends to keep the hoppercool'.

Principle of operation When main switch 89 is closed, a source ofcurrent supply 94 is connected to the line side of each of the solenoidwindings 19, 80, 84- and 85. During the last phase of the cycle ofoperations, solenoid 19 was energized to cause the piston rod 8| to moveout of its cylinder 95 thereby telescoping each sleeve cutter 35 overits associated forming die 39, into a position substantially as shown bythe dot-and-dash line in Fig. l of the drawings, to sever and releasethe formations of plastic material 4|. As the piston rod 8| ofservo-motor 64 reaches the end of its outward stroke, the projection 82on the piston rod 8| closes contact switch 83 to complete an electricalcircuit for energizing the solenoid winding 84 of servo-motor 61 toinitiate the next operating cycle. Solenoid B4 is electro-magneticallyenergized thus actuating solenoid plunger 14 to rock the common rockingshaft 15 and drive piston 69 into its associated cylinder 68substantially as shown in Fig. 1 of the drawings, thus supplyingcompressed air from compressed air supply pipe 66 through connectingport 19 -to the front compartment of pneumatic cylinextrusion so formed,and a slide valve reciprocably operable in the passageway to uncover oneof said ports to reduce the pressure at the lower end of the feed hopperbelow atmospheric to draw a charge of plastic material from the feedhopper into the passageway and then sealing off the lower end of thehopper and uncovering the other port to apply compressed air to thepassageway to move said charge of plastic material towards the exit.

3. In an extrusion machine a gravity feed hopper for plastic material,an exit passageway connecting with the bottom of said hopper throughwhich the plastic material is caused to be progressed to extrusion, asource of pressure below atmospheric, a source of compressed air, eachof said sources having a separate ported opening connecting with saidpassageway, forming and cutting die mechanism mounted at the exit of thepassageway said die mechanism being operable to form a plastic extrusionand to close said eXit to sever and release said extrusion, and mountedin said passageway to alternately uncover one of said ported openings toreduce the pressure at the bottom of the hopper below atmospheric todisplace a charge of the plastic material from the feed hopper into thepassageway and then to seal off the feed hopper from the passageway anduncover the other ported opening to raise the pressure in the passagewaysubstantially above atmospheric to move said charge towards the formingand cutting die.

4. In a self-contained extrusion machine unit and in combination a feedhopper for plastic material, a pedestal for supporting said hopper, saidhopper and pedestal being fabricated in one self-contained unit, saidpedestal being hollow, the lower wall of said hopper and the side wallsof said pedestal in conjunction forming a housing, said hopper having athroated passage at its lower end, an extrusion outlet including aforming and cutting die merging with and in continuation of saidthroated passage, a chamber for compressed air having a port openinginto said throated passage, a sleeve valve slidably operable in thethroated passage from closed to open position and back again, saidsleeve valve when in closed position sealing olf the hopper anduncovering the port to permit compressed air to enter said throatedpassage and eXtrude a quantity of plastic material over the forming die,said sleeve valve when in open position sealing off the compressed airchamber and eiTecting the release of the compressed air from thethroated passage to permit the movement of plastic material from saidhopper into said extrusion outlet, electro-pneumatic servomotors mountedwithin and protected by said housing, a plurality of rocker armsrockably supported upon the structure of the self-contained unit, andsaid rocker arms being mechanically coupled to and rockable by saidservo-motors to operate said sleeve valve and said cutting die inpredetermined cyclic order to complete the self-contained extrusionmachine unit.

5. In a self-contained extrusion machine unit and in combination a feedhopper having a throated passage, an air chamber having a port extendingthrough the wall thereof into said throated passage, and a hollowpedestal for supporting said hopper said throated passage and said airchamber, said feed hopper, throated passage, air chamber and hollowpedestal all being cast in one unit, the lower wall of the feed hopperand the side walls of the pedestal in conjunction forming a chamberedhousing disposed beneath said feed hopper, said air chamber beingsuppliable with air at a pressure above atmospheric, an extrusion outletincluding a forming and cutting die merging with and in continuation ofsaid throated passage, a sleeve valve slidably operable in the throatedpassage from closed to open position and back again, said sleeve valvewhen in closed position sealing off the hopper and uncovering the portto allow air under pressure to enter said throated passage from said airchamber and extrude a quantity of plastic material over the forming die,said sleeve valve when in open position sealing off the air chamber andeiecting the discharge of the compressed air from the throated passageand the subsequent movement of plastic material from said hopper intosaid extrusion outlet, electro-pneumatic servo-motors mounted within andprotected by said chambered housing, a plurality of rocker arms rockablysupported upon the structure of the unit casting, and said rocker armsbeing mechanically coupled to and rockable by said serve-motors tooperate said sleeve valve and said cutting die in properly timedsequence to complete said self-contained extrusion machine unit.

FRANK R. SCHMITT.

REFERENCES CITED rThe following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 535,179 Bloemeck June 29, 18971,925,559 Bliss May 7, 1912 1,306,966 Marcoux et al. June 17, 19191,656,642 Mosher Apr. 26, 1932 1,899,362 Stratton Feb. 28, 19332,166,269 Mosher July 18, 1939 2,246,758 Roth June 24, 1941 2,273,595Roth Feb. 17, 1942 2,317,897 Ellis Apr. 27, 1943 2,339,291 Paulus et alJan. 18, 1944 2,397,351 Heintz et al. Mar. 26, 1946 Certificate ofCorrection Patent No. 2,511,826 June 13, 1950 FRANK R. SCHMITT It ishereby certified that errors appear in the printed specification of theabove numbered patent requiring correction as follows:

Column 7, line 49, for switch 3 read switch 83; column 9, line 20, afterthe word passageway insert a comma; line 23, before mounted insert areciprocating valve; column 10, line 38, for serve-motors readservo-motors;

and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the case in thePatent Office.

Signed and sealed this 19th day of September, A. D. 1950.

[smi] THOMAS F. MURPHY,

Assistant Oommzssoner of Patente.

